/* Direct Heating Installations — demo stylesheet (Wave 1, V0.4).
   Art direction: "heat-circuit field guide". Light-dominant editorial page.
   Deep graphite ink on warm mineral white, oxidised copper hairline rules,
   a discrete cool-blue-to-amber temperature band used as a structural rule,
   and one controlled ember-orange accent reserved for the call action. */

:root {
  --ink: #17191c;
  --ink-2: #24282c;
  --body: #3c4349;
  --paper: #f6f3ec;
  --paper-2: #fbfaf6;
  --mineral: #79776e;
  --line: #ded7c8;
  --line-soft: #eae4d7;
  --copper: #a8623c;
  --copper-soft: #cfae94;
  --ember: #cd4318;
  --ember-dark: #ac3611;
  --blue: #3f6f8c;
  --dark: #14181b;
  --dark-2: #0f1214;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--body);
  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.55;
  overflow-wrap: break-word;
}

h1, h2, h3 {
  margin: 0;
  color: var(--ink);
  font-weight: 800;
  letter-spacing: -0.024em;
  line-height: 1.05;
}

p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
svg { display: block; }

.micro {
  margin: 0;
  color: var(--mineral);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.7rem;
  letter-spacing: 0.17em;
  text-transform: uppercase;
}

.wrap {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 34px;
}

/* ---------- temperature band (structural rule motif) ---------- */

.tempscale {
  display: flex;
  height: 6px;
  margin-top: 56px;
}

.tempscale span { flex: 1 1 0; }

.tempscale span:nth-child(1) { background: #44759a; }
.tempscale span:nth-child(2) { background: #5f8fa2; }
.tempscale span:nth-child(3) { background: #86a39d; }
.tempscale span:nth-child(4) { background: #b3ae97; }
.tempscale span:nth-child(5) { background: #d1a878; }
.tempscale span:nth-child(6) { background: #dba05a; }
.tempscale span:nth-child(7) { background: #dd9a4b; }

.tempscale--thin { height: 3px; margin-top: 22px; }

.tempscale--dark { margin-top: 0; margin-bottom: 52px; opacity: 0.85; }

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(246, 243, 236, 0.96);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 70px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  min-height: 44px;
  color: var(--ink);
  font-size: 1.02rem;
  font-weight: 800;
  letter-spacing: -0.012em;
}

.brand-mark svg {
  width: 26px;
  height: 26px;
  fill: none;
  stroke: var(--ink);
  stroke-width: 1.7;
}

.brand-mark .mark-loop { stroke: var(--copper); stroke-dasharray: 3.4 2.6; }
.brand-mark .mark-node { fill: var(--paper); stroke: var(--ink); }

.site-nav { margin-left: auto; }

.site-nav ul { display: flex; gap: 26px; }

.site-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  color: #43494e;
  font-size: 0.84rem;
  letter-spacing: 0.01em;
  border-bottom: 1px solid transparent;
}

.site-nav a:hover { color: var(--ink); border-bottom-color: var(--copper); }

.header-call {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  background: var(--ember);
  color: #fff;
  font-size: 0.9rem;
  font-weight: 700;
  border-radius: 1px;
}

.header-call:hover { background: var(--ember-dark); }

.menu-toggle { display: none; }

/* ---------- hero ---------- */

.hero {
  padding: 78px 0 0;
  background: var(--paper);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.22fr) minmax(0, 0.78fr);
  gap: 62px;
  align-items: end;
}

.hero-copy { padding-bottom: 8px; }

.hero-copy .micro {
  padding-bottom: 22px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 26px;
}

.hero h1 {
  font-size: clamp(2.5rem, 4.8vw, 4.05rem);
  margin-bottom: 20px;
}

.hero-lede {
  max-width: 34ch;
  color: var(--ink-2);
  font-size: 1.08rem;
  line-height: 1.5;
  margin-bottom: 34px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 20px;
}

.btn-call {
  display: inline-flex;
  align-items: center;
  gap: 13px;
  min-height: 58px;
  padding: 0 24px;
  background: var(--ember);
  color: #fff;
  border-radius: 1px;
}

.btn-call:hover { background: var(--ember-dark); }

.btn-call-label {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  opacity: 0.82;
}

.btn-call-number { font-size: 1.16rem; font-weight: 800; letter-spacing: 0.01em; }

/* the header keeps its compact control size while still being a call control */
.header-call.btn-call { min-height: 44px; padding: 0 18px; gap: 0; border-radius: 1px; }

.btn-quiet {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--ink);
  font-size: 0.92rem;
  font-weight: 700;
  border-bottom: 2px solid var(--copper-soft);
}

.btn-quiet:hover { border-bottom-color: var(--copper); }

.hero-figure { margin: 0; }

.hero-figure .circuit { width: 100%; height: auto; }

.hero-figure figcaption {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  text-align: right;
}

.circuit .spine path {
  fill: none;
  stroke: var(--ink);
  stroke-width: 2.4;
}

.circuit .return-run path {
  fill: none;
  stroke: var(--copper);
  stroke-width: 1.7;
  stroke-dasharray: 9 7;
}

.circuit .cross-run path {
  fill: none;
  stroke: var(--blue);
  stroke-width: 1.6;
  stroke-dasharray: 4 4;
}

.circuit .flow-head { fill: var(--copper); }

.circuit .flow-head-cool { fill: var(--blue); }

.circuit .junctions circle { fill: var(--paper); stroke: var(--ink); stroke-width: 1.6; }

.circuit .nodes circle { fill: var(--paper); stroke: var(--ink); stroke-width: 2.2; }

.circuit .nodes .node-core { fill: var(--copper); stroke: none; }

.circuit .node-labels text {
  fill: var(--copper);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 18px;
  letter-spacing: 0.08em;
}

/* ---------- services index ---------- */

.services {
  padding: 76px 0 0;
  background: var(--paper-2);
  border-top: 1px solid var(--line);
}

.section-head h2 {
  font-size: clamp(1.7rem, 2.5vw, 2.3rem);
  margin-top: 14px;
}

.index { margin-top: 54px; }

.index-row {
  display: grid;
  grid-template-columns: 92px minmax(0, 0.82fr) minmax(0, 2fr);
  column-gap: 34px;
  padding: 28px 0 30px;
  border-top: 1px solid var(--line);
}

.index-row--last { border-bottom: 1px solid var(--line); }

.index-rail { border-left: 1px solid var(--copper); padding-left: 18px; }

.index-num {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 1.3rem;
  letter-spacing: 0.04em;
  color: var(--copper);
}

.index-group h3 {
  font-size: 1.16rem;
  letter-spacing: -0.018em;
  padding-top: 6px;
}

.index-labels {
  display: flex;
  flex-wrap: wrap;
  align-content: flex-start;
  max-width: 644px;
}

.index-labels li {
  padding: 7px 16px;
  border-left: 1px solid var(--line-soft);
  color: var(--body);
  font-size: 0.94rem;
  line-height: 1.35;
}

/* ---------- secondary plumbing row ---------- */

.also {
  padding: 34px 0 44px;
  background: var(--paper-2);
}

.also-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 28px;
}

.also h2 {
  color: var(--mineral);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.also-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 26px;
  margin-left: auto;
}

.also-list li {
  color: #5b6167;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 3px;
}

/* ---------- contact ---------- */

.contact {
  background: var(--dark);
  color: #d6d2c8;
  padding: 52px 0 62px;
}

.contact .micro { color: #9a9382; }

.contact-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
  gap: 40px;
  align-items: end;
}

.contact h2 {
  color: #f7f4ec;
  font-size: clamp(1.75rem, 2.7vw, 2.4rem);
  margin: 14px 0 18px;
}

.contact-address {
  color: #b9b3a6;
  font-size: 1.02rem;
  border-top: 1px solid rgba(255, 255, 255, 0.16);
  padding-top: 16px;
  max-width: 34ch;
}

.contact-action { display: flex; justify-content: flex-end; }

.btn-call-invert { box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.14); }

.btn-call-invert .btn-call-label { opacity: 0.9; }

/* ---------- footer ---------- */

.site-footer {
  background: var(--dark-2);
  color: #b6b1a6;
  padding: 44px 0 26px;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px 40px;
  padding-bottom: 26px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.footer-name {
  color: #f4f1e9;
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: -0.012em;
}

.footer-phone {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  margin-top: 4px;
  color: #f4f1e9;
  font-size: 1rem;
  font-weight: 700;
  border-bottom: 1px solid rgba(255, 255, 255, 0.24);
}

.footer-phone:hover { border-bottom-color: var(--ember); }

.footer-nav { margin-left: auto; }

.footer-nav ul { display: flex; flex-wrap: wrap; gap: 22px; }

.footer-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  font-size: 0.85rem;
  color: #a9a396;
}

.footer-nav a:hover { color: #fff; }

.footer-base { padding-top: 20px; }

.footer-base p { color: #7d786d; font-size: 0.78rem; }

/* ---------- fixed mobile call bar ---------- */

.mobile-call { display: none; }

@media (max-width: 900px) {
  .wrap { padding: 0 20px; }

  .tempscale { margin-top: 34px; }
  .tempscale--thin { margin-top: 18px; }
  .tempscale--dark { margin-top: 0; margin-bottom: 34px; }

  .header-inner { gap: 12px; min-height: 64px; }

  .brand { font-size: 0.78rem; letter-spacing: 0; gap: 8px; }

  .brand-mark svg { width: 22px; height: 22px; }

  .header-call { display: none; }

  .menu-toggle {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 40px;
    margin-left: auto;
    padding: 0 12px;
    background: transparent;
    color: var(--ink);
    border: 1px solid var(--line);
    border-radius: 1px;
    font: inherit;
    font-size: 0.76rem;
    font-weight: 700;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    cursor: pointer;
  }

  .menu-bars {
    width: 15px;
    height: 2px;
    background: var(--ink);
    box-shadow: 0 -5px 0 var(--ink), 0 5px 0 var(--ink);
  }

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin: 0;
    background: var(--paper-2);
    border-bottom: 1px solid var(--line);
  }

  .site-header.nav-open .site-nav { display: block; }

  .site-nav ul { flex-direction: column; gap: 0; padding: 6px 20px 14px; }

  .site-nav a {
    min-height: 46px;
    width: 100%;
    border-bottom: 1px solid var(--line-soft);
  }

  .hero { padding: 40px 0 0; }

  .hero-grid { grid-template-columns: minmax(0, 1fr); gap: 34px; align-items: start; }

  .hero-copy { padding-bottom: 0; }

  .hero-copy .micro { padding-bottom: 14px; margin-bottom: 18px; }

  .hero h1 { font-size: clamp(1.8rem, 8vw, 2.45rem); }

  .hero-lede { font-size: 1rem; margin-bottom: 26px; }

  .hero-actions { gap: 12px; }

  .btn-call { min-height: 56px; padding: 0 18px; width: 100%; justify-content: center; }

  .btn-quiet { min-height: 40px; }

  .hero-figure { max-width: 268px; margin: 0 auto; }

  .hero-figure figcaption { text-align: center; }

  .services { padding: 46px 0 0; }

  .section-head h2 { margin-top: 10px; }

  .index { margin-top: 30px; }

  .index-row {
    grid-template-columns: minmax(0, 1fr);
    column-gap: 0;
    row-gap: 14px;
    padding: 20px 0 22px;
  }

  .index-rail {
    border-left: 0;
    border-top: 1px solid var(--copper);
    padding: 10px 0 0;
    display: flex;
    align-items: center;
    gap: 12px;
  }

  .index-num { font-size: 0.95rem; }

  .index-group h3 { font-size: 1.04rem; padding-top: 0; }

  .index-labels { flex-direction: column; align-items: stretch; }

  .index-labels li {
    padding: 7px 0 7px 16px;
    border-left: 1px solid var(--copper-soft);
    font-size: 0.9rem;
  }

  .also { padding: 26px 0 32px; }

  .also-inner { gap: 10px 20px; }

  .also-list { margin-left: 0; gap: 8px 20px; }

  .also-list li { font-size: 0.86rem; }

  .contact { padding: 34px 0 42px; }

  .contact-inner { grid-template-columns: minmax(0, 1fr); gap: 24px; align-items: start; }

  .contact h2 { font-size: 1.6rem; margin: 10px 0 14px; }

  .contact-address { font-size: 0.96rem; padding-top: 12px; }

  .contact-action { justify-content: flex-start; }

  /* clearance for the fixed call bar (applied to the footer element itself) */
  .site-footer { padding: 34px 0 104px; }

  .footer-inner { flex-direction: column; align-items: flex-start; gap: 18px; padding-bottom: 22px; }

  .footer-nav { margin-left: 0; }

  .footer-nav ul { gap: 18px; }

  .mobile-call {
    display: block;
    position: fixed;
    left: 12px;
    right: 12px;
    bottom: 0;
    z-index: 60;
    visibility: hidden;
    opacity: 0;
    transform: translateY(140%);
    pointer-events: none;
    transition: transform 0.28s ease, opacity 0.28s ease, visibility 0.28s ease;
  }

  .mobile-call.is-visible {
    visibility: visible;
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }

  .mobile-call a {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    min-height: 58px;
    padding: 0 18px;
    background: var(--dark);
    color: #f7f4ec;
    border-radius: 2px;
    border-top: 1px solid var(--ember);
    box-shadow: 0 10px 26px rgba(15, 18, 20, 0.3);
  }

  .mobile-call-label {
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-size: 0.68rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #a09a8c;
  }

  .mobile-call-number { font-size: 1.04rem; font-weight: 800; }
}